Corroded Battery Cable Replacement (tons of pics/summary)

[bimmerjeeper]

My cables were very corroded. Even the bolts were frozen solid. I replaced them today.
I decided to spend some time writing this up in the style I find most useful.
If you like this better than "Disconnect all wires. Replace new wires. Drink beer!" then let me know.
Yea, for most guys here, this job is too basic to bother writing up.
I am new to working on cars, and need all the details and photos I can get.
Also, I like to know what I am getting into before I try to tackle a job.
As you all know, there's always a few gotcha that can ruin you.
Hopefully, this post can help other new guys who are wondering if they can replace their cables by themselves.

This job was suitable for a beginner. Nothing got stuck, and it was just turning bolts. It took me a couple of hours.
This is because on a new project, you spend a lot of time figuring out what you're looking at, and what order to do things in, etc.
If I did this again, I could do it in 45 mins.

BEFORE

I ordered a set of 4AWG cables for $80 from Jon at http://www.kelleyswip.com/price.html. They were precut to my year of XJ.
He answered all my questions patiently. (And I had a lot, believe me) I felt good about sending my business his way.
He is a good man, and any 1-man shop is a labor of love that involves countless investment of time for minimal payback.

The 5 cables are as follows:

1. (+) to Starter Motor
2. (+) to fuse box/PDC
3. (-) to Engine Block
4. (-) to Fender
5. Braided cable from rear of Engine Block to Firewall

Tools needed:

• Metric and SAE sockets and wrenches
• Long flathead screwdriver (to pry off battery posts)
• Utility knife
• Dielectric grease (for all cable connections)
• Wire stripper (optional)
• PB Blaster (optional)
• Heat gun (optional)
• Electrical tape

All bolts came off with no problem. I did use PB Blaster just in case. My battery cables needed to be pried off with a long screwdriver. I used all metric sockets and wrenches (8mm, 13mm, 14mm). I also used wrenches for some tight fits where a ratchet head would not fit. Be patient here, b/c you might only get 1 or 2 clicks on the ratchet with each turn. I got a pillow to rest my neck while undoing the blots 1/8 turn at a time! I also used a 3/8" wrench for the fender ground wire.

 

[bimmerjeeper]

Let's start!

First, you need to separate the indiv. cables from the "octopus" loom where the battery cables go into.
(This was daunting at first, b/c now you're hacking up your XJ. IT turned out to be no big deal)
There are about 7-8 wires and cables all taped together.
2 of the cables in the loom will be replaced. All others will be left intact.
You will need to slice open the loom with a utility knife. This took the most time. Be patient.
I did a combination of unravelling the tape and just slicing through it with a utility knife.

Purple goes to starter
Green goes to engine block
Red goes to alternator

In this angle, the bottom 2 go to the alternator.
The 2 going to the right go to the engine block.
The one going "up" is the (+) going down to the starter

Once everything is separated out of the loom, we can start to detach individual cables.

Cable 1
The main (+) cable goes into the loom and down to the starter.
So, let's look at the starter/solenoid under the car.

You will remove 2 bolts to remove a "block" that holds 2 cables.
In this photo, you remove the top 2 bolts. They are now detached.

Also, I unbolted this clamp guide thing. Once the cables are out, remove this clamp for reuse on the new cables. You now fish out these 2 wires.

Since the thin green wire comes from the loom and not the battery, you need to reuse this. Since the block is fused to the old (+) cable you're replacing, you'll need to cut away the thin green wire for reuse. Again, we're throwing away the red, but keeping the green (b/c the green does NOT come from the battery)

(This was the moment of truth. Now, there's no going back!)

NOTE: 2 mistakes here
1) I forgot to thread the heatshrink before crimping on the eyelet lug hole.
2) I think I pushed too much wire through the crimp area. See the excess. This would be exposed wire.

(There is a heatshrink sealer that I forgot to photograph)

Now attach the new (+) cable and the existing green wire back to the starter solenoid.

Don't forget to reattach the "guide" and feed the 2 wires through.

 

[bimmerjeeper]

Cable 2
The other (+) cable goes to the front of the fusebox/PDC
The green cable on the left is not what we replace.
It's the cable on the right that turns straight down.
The new one goes straight out (which leaves one minor issue: How to put back that little cover that goes over this area)

Red cable was a bit long, so I looped it.

Cable 3
The main (-) cable goes to the engine block.
Here is the view from underneath.
The (-) cable goes to the bolt on the right.
(The other stuff is for the alternator, which I left alone)

Cable 4
Negative ground goes to the fenderwell.

(Cable 5 not yet done)

Here is the final result!

Appendix:
I was curious how deep the corrosion goes up the cable, so I sliced it open.
It turns out it really doesn't travel up the cable, but it does crack the inner wires at the connection point.
About 1/3 of my wires were cracked off.

 

[kastein]

Just one nitpick - you really should be using a better crimper for that ring terminal than a pair of needlenose pliers, that's not a secure connection. I'm partial to the ratchet crimper style - http://www.amazon.com/Ratcheting-Crimp-Tool-Insulated-Terminals/dp/B0002KR9GQ for example. I generally use the slot for red terminals for reds and blues since it gives a more secure crimp. Also, I strongly suggest sealant lined heatshrink crimp terminals such as http://www.amazon.com/Pico-2225PT-E...ectronics&ie=UTF8&qid=1352691140&sr=1-8-spell - they're much more corrosion resistant.

 

[WB9YZU]

Nice Write-Up. I'm sure someone will find it handy.



Yah, a pliers makes a bad crimper. They make inexpensive crimp tools you can pick up at the HWstore. I solder and heat shrink all my crimp connectors in vital areas.

 

[bimmerjeeper]

Thank you for that nitpick. I did not feel that it was too secure either. I ended up using 3 different pliers to really squeeze it. It finally seemed secure after that. I wrapped up the connection with electrical tape b/c I forgot to thread the heatshrink before crimping the lug hole. I also folded back that excess wire and pressed it down, so it is now hooked around that connection hole. Regardless, I will borrow a crimper and do it again to reinforce.

 

[88trailcrawler]

When I did mine I couldn't get the nut off the stud down by the dipstick, the stud spun out of the block. I had to cut the big ground (no biggie because it was going to be replaced) and the four small sensor grounds in order to spin the stud out.

The sensor wires were short and the stud difficult to reach, I couldn't rely on new crimp on connectors way down there. I got the big ground back on secure, but the four small wires were just to fragile down there

I bought a short (6 port) residential ground bus at Home Depot. I screwed the ground bus to the fire wall passenger side. Ran a 10 gauge ground from the bus to the firewall ground bolt. Then brought the 4 sensor grounds up to the mounted ground bus.

Created a secure, accessible ground, plus makes nice ground for multi meter testing and I now have a place to secure a few more ground wires if needed.

 

[bimmerjeeper]

That sounds like a nightmare.
1 bolt at the front engine block.
On my 1998, it came off very easily.

 

[bobbygentryjr]

Awesome write-up. Exactly what I was looking for before I tackle this project. Thanks!

 

[alex673]

Excellent write up man! Thankyou!!!

 

[Ecomike]

Jon (5-90) should hire you to write manuals, LOL.

One thing you should add for sure is the Jeep info, like 1998 XJ IIRC? This job is way different on the older Renix XJ jeeps like mine. You will find a standard wiring tool ($6 apx), worth the money, combination wire stripper and crimper.

Also I use electricians self vulcanizing silicon or rubber tape, not PVC electrical tape under the hood. The standard indoor PVC electricians tape does not hold up.

They look like this one:

http://www.ebay.com/itm/175-Pc-Sold...196?pt=LH_DefaultDomain_0&hash=item3f1f93cf44

Just about any hardware, automotive, electrical supply, Wallyworld store carries them.

Sealing tape:

http://www.uline.com/BL_6422/Silico...ricode=WK713&gclid=CPib0KuSp7QCFa5QOgodkVQAPQ

http://www.uline.com/Product/Detail...&gadtype=pla&gclid=CPCN9M2Sp7QCFcp9OgodKkoAig

I also use small amounts of liquid electricians tape and automotive silicone in a tube for small spots.

 

[xcm]

Jon (5-90) should hire you to write manuals, LOL.

5-90 writes books, and calls them posts, he'll be fine =)

 

[Ecomike]

5-90 writes books, and calls them posts, he'll be fine =)

Ya, I know. 5-90 was one of my early Renix mentors 6 years ago. But I don't see many photos from him. Lately you can fire up youtube and show a five year old how to swap an engine, LOL. But the videos can be oh so tedious to watch till you get the one piece of info you want. Especially when they spend 5 minutes showing you how to open the hood first, LOL!!!

 

[bimmerjeeper]

EcoMike, thanks. Jon answered a ton of questions about this job before I felt comfortable in doing it. He had never done this on a 1998, so stuff like cutting open the loom was not in his 1 page PDF with no photos. His directions could have used a ton of detail, so, this write-up was my way of thanking him for the time he spent trying to explain all the steps, in hopes that he can reuse it for all future clueless customers.

Like EVERY job, it now seems dead stupid simple in hindsight, but is daunting when you have no idea what you're getting into. And yes, this write up is at the "idiot proof" that beginners really need to have confidence in tacking something new. One could only wish all write-ups could have this much detail in them.

Yea, I screwed up the crimp step and the heat shrink step. I am going to eventually install a new starter (just because) and when I do that, I will recut and crimp/seal that connector lug.

 

[bigalpha]

When I did mine I couldn't get the nut off the stud down by the dipstick, the stud spun out of the block. I had to cut the big ground (no biggie because it was going to be replaced) and the four small sensor grounds in order to spin the stud out.

This happened on my 88 MJ, too. Talk about a PITA.

I bought a short (6 port) residential ground bus at Home Depot. I screwed the ground bus to the fire wall passenger side. Ran a 10 gauge ground from the bus to the firewall ground bolt. Then brought the 4 sensor grounds up to the mounted ground bus.

This is an excellent idea. I wish that I would have done this.

 

[kastein]

I would suggest mounting it to the block instead of the firewall for vibration reasons (that 10ga wire better be auto grade fine stranded wire or it will eventually break from flexing/vibration) but the ground bar is an interesting idea.

 

[Pelican]

I use tinned marine grade wire for situations involving high flex/vibration. I'm also using 2awg marine wire for replacement battery cables. Overkill perhaps for anyone not living in a corrosive environment but I love this stuff.

genuinedealz.com

"Free" shipping and they will assemble and crimp cables for $1 per end if you buy the components.

 

[88trailcrawler]

I would suggest mounting it to the block instead of the firewall for vibration reasons (that 10ga wire better be auto grade fine stranded wire or it will eventually break from flexing/vibration) but the ground bar is an interesting idea.

It's screwed into the firewall set in a bead of silicon. The wire is just now regular construction wire. (Kinda ghetto looking). I would think mounting to the block would subject it to more vibration, plus your installation points are limited.

Point is that it is easily accessible for inspection and repair. It grounds to the back head ground bolt AND a hood hinge bolt. The wires run along the firewall under the cowl. It's going to take some time before vibration breaks them down.

Not an ideal restoration grade solution, but certainly cheap, easy and effective.

 

[kastein]

The problem is that one end of that 10ga wire as I understand it is connected to the block and the other to the firewall... the vibration of the engine and body is different so the wire will constantly flex slightly till it breaks. If you bolt the ground strip to the block, there's no flexing because they vibrate together, and it won't break the wire.

It might take years... might take months. eventually it'll break.

 

[88trailcrawler]

The problem is that one end of that 10ga wire as I understand it is connected to the block and the other to the firewall... the vibration of the engine and body is different so the wire will constantly flex slightly till it breaks. If you bolt the ground strip to the block, there's no flexing because they vibrate together, and it won't break the wire.

It might take years... might take months. eventually it'll break.

The ground buss is mounted on the firewall. The ECU/TCU sensor grounds exit the harness and go straight to the new ground buss instead of the problematic bolt on the block.

I then ran the 10 gauge from the new ground buss to the factory ground bolt on the firewall just behind the valve cover AND to a hood hinge bracket. The new wire only runs along the top of the firewall. There are no new wires going to the block.